It's been a while since I owned a car and we have just purchased a second hand one today (Woot!)

I am a bit bamboozled about car insurance as there seems to be a lot more choice these days since I last looked into it.

Are there any things I should be aware of to make the decision of who to go with easier?

Bundling with house insurance?
Online companies vs traditional companies?
Any pitfalls to be wary of?

Who do you insure with and why??